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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | -1 |
| 3 | 19 |
| 4 | -54 |
| 5 | 1093 |
| 6 | -7350 |
| 7 | 163231 |
| 8 | -1890840 |
| 9 | 46856629 |
| 10 | -793522800 |
| 11 | 22080566781 |
| 12 | -495344954280 |
| 13 | 15484604767435 |
| 14 | -431828053264608 |
| 15 | 15117468706455571 |
| 16 | -502151660656769760 |
| 17 | 19584866374955872169 |
[0,2,-1,19,-54,1093,-7350,163231,-1890840, 46856629,-793522800,22080566781,-495344954280, 15484604767435,-431828053264608,15117468706455571, -502151660656769760,19584866374955872169] |